JP4734694B2 - Biaxially stretched polyester film for molding process and molded laminate - Google Patents

Description

【００７１】
【表２】

【００７２】
【表３】

【００７３】
【表４】

【００７４】
なお、表中の記号は次の通りである（数値は酸、グリコール成分の中のモル％）。
【００７５】
ＴＰＡ：テレフタル酸
ＩＰＡ：イソフタル酸
ＥＧ：エチレングリコール
ＤＥＧ：ジエチレングリコール
ＣＨＤＭ：シクロヘキサンジメタノール
ＮＤＣ：ナフタレンジカルボン酸
Ｍ：フィルム中に残存する触媒金属元素の濃度（ミリモル％）
Ｐ：フィルム中に残存するリン元素の濃度（ミリモル％）を示す。）
Ｔｉ／Ｓｉ：チタン、シリカ複合酸化物
Ｇｅ：ゲルマニウム化合物
Ｓｂ：アンチモン化合物
Ｃａ：カルシウム化合物
【００７６】
【発明の効果】
本発明の成形加工用二軸延伸ポリエステルフィルムは、単体または非金属素材と積層した際の成形加工性、耐衝撃性、耐熱性、美麗性に優れており、多くの成形加工用素材に好適に使用することができる。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a biaxially stretched polyester film for molding.
[0002]
Specifically, it is not only excellent in moldability when used as a material that is molded alone or in a laminated configuration with non-metallic materials, but also in the heat resistance and beauty of the final product. The present invention relates to a biaxially stretched polyester film.
[0003]
[Prior art]
Biaxially stretched polyester film has excellent heat resistance, mechanical properties, and electrical properties, so it can be used as a base film for magnetic recording materials, electrical insulating materials, coating materials, industrial materials such as photographic film base films, and printing. It is widely used for packaging materials because of its excellent properties and vapor deposition.
[0004]
In recent years, applications of biaxially stretched polyester films have become increasingly diversified, and examples of use in molding applications have been seen.
[0005]
For example, while a conventional coating can uses a large amount of solvent and water for cleaning, a steel plate, an aluminum plate, or a metal plate that has been subjected to various surface treatments such as plating on the metal plate. Has been proposed, and a high rate copolymerized PET (polyethylene terephthalate) film described in JP-A-3-110124 is used.
[0006]
Furthermore, as an example of using the biaxially stretched polyester film as a single body or a laminate, for example, as shown in Japanese Patent No. 2611415, Japanese Patent Laid-Open No. 4-1022, and Japanese Patent Laid-Open No. 4-1023, It has been proposed to use a rate copolyester biaxially stretched to obtain a film having a specific crystal size and a degree of plane orientation, and to be used for a film for molding transfer and a film for molding container.
[0007]
However, since the film for laminating a metal plate shown above is used by laminating with a metal, it is essential to include a metal plate in order to use it as a molding material in combination with other materials. It is difficult not only to reduce the weight, but also has a drawback that the forming method is narrowly limited. Moreover, since the high rate copolymerized PET is used, there is a problem that the heat resistance and impact resistance of the final product to be obtained are lowered and the beauty is inferior.
[0008]
In addition, in the example where the biaxially stretched polyester film shown above is used for molding in a single body or a laminate, since a high-copolymerized polyester is used, the moldability is excellent, but the heat resistance of the final product to be obtained is high. There is a problem that the property and impact resistance are lowered, and the beauty is inferior.
[0009]
[Problems to be solved by the invention]
The object of the present invention is to eliminate the above-mentioned problems of the prior art, and has excellent molding processability, particularly embossing processing, vacuum forming, pressure forming, squeeze forming, bending forming, stretch forming, etc. An object of the present invention is to provide a biaxially stretched polyester film for molding process that is excellent in molding processability.
[0010]
[Means for Solving the Problems]
The object of the present invention described above is characterized in that a polyester having a melting point of 210 to 280 ° C. is a main component, satisfies the following formula (1), and is molded by a single layer or a laminated structure with a nonmetallic material. Biaxially stretched polyester film And a biaxially stretched polyester film for molding with a haze change rate of 0 to 20% after heating at 170 ° C. for 10 minutes Can be achieved.
[0011]
(S1 + S2) / 2 ≧ 300% (1)
S1, S2: Longitudinal breaking elongation (%) and width breaking elongation (%) are measured within the range of 20 ° C. to (melting point−60) ° C., and the values when the sum becomes maximum are respectively S1 , S2.
[0012]
As a result of intensive studies, the present inventors use a high-melting polyester having a melting point of 210 ° C. to 280 ° C. and obtain a biaxially stretched film having a breaking elongation of 300% or more. It has been found that a molded product with excellent high-temperature molding processability and whitening resistance when molded with a laminated structure of the above, and excellent heat resistance (a property that can prevent whitening when contacted with a high-temperature body) can be obtained. In particular, it is possible to provide a biaxially stretched polyester film for molding which is excellent in molding processability such as embossing, vacuum forming, pressure forming, and squeeze forming.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
The polyester constituting the biaxially stretched polyester film of the present invention is a general term for polymers having an ester bond as the main bond in the main chain, and usually by polycondensation reaction between a dicarboxylic acid component and a glycol component. Obtainable.
[0014]
Here, examples of the dicarboxylic acid component include aromatic dicarboxylic acids such as terephthalic acid, naphthalene dicarboxylic acid, isophthalic acid, diphenyl dichanrubonic acid, diphenyl sulfone dicarboxylic acid, diphenoxyethane dicarboxylic acid, 5-sodium sulfone dicarboxylic acid, and phthalic acid. Acid, oxalic acid, succinic acid, adipic acid, sebacic acid, dimer acid, maleic acid, fumaric acid and other aliphatic dicarboxylic acids, cyclohexanedicarboxylic acid and other alicyclic dicarboxylic acids, paraoxybenzoic acid and other oxycarboxylic acids Can be used. Examples of the glycol component include aliphatic glycols such as ethylene glycol, propanediol, butanediol, pentanediol, hexanediol, and neopentylglycol, polyoxyalkylene glycols such as diethylene glycol, polyethylene glycol, and polypropylene glycol, and cyclohexanedimethanol. Alicyclic glycols, aromatic glycols such as bisphenol A and bisphenol S, isosorbide, and the like can be used.
[0015]
In the present invention, it is necessary that the melting point of the polyester is 210 to 280 ° C. in order to obtain a film having both heat resistance and molding processability and excellent in beauty. Particularly in applications where heat resistance and aesthetics are important, if the melting point is low, foreign matter is likely to be generated due to insufficient heat resistance of the polyester in the film production process. Therefore, the melting point is preferably 220 to 280 ° C, particularly preferably. It is 246-280 degreeC.
[0016]
In particular, 93 mol% or more of the acid component constituting the polyester is preferably a terephthalic acid component and / or a naphthalenedicarboxylic acid component from the viewpoint of molding processability and heat resistance, and more preferably 95 mol% or more.
[0017]
Of these glycol components, ethylene glycol, cyclohexanedimethanol, and isosorbide are preferable from the viewpoint of heat resistance and molding processability, and 95 mol% or more of the glycol component constituting the polyester is ethylene glycol, cyclohexanedimethanol, It is preferably isosorbide, more preferably 97 mol% or more.
[0018]
Catalysts for producing the polyester of the present invention include alkaline earth metal compounds, manganese compounds, cobalt compounds, aluminum compounds, antimony compounds, titanium compounds, titanium / silica composite oxides, titanium / zirconia composite oxides, and germanium compounds. Etc. can be used. Furthermore, phosphorus compounds can be used as heat stabilizers.
[0019]
For example, when adding a catalyst comprising an alkaline earth metal or a titanium compound catalyst as a catalyst, after reacting dimethyl terephthalate and ethylene glycol in the presence of an alkaline earth metal catalyst to form bishydroxyethyl terephthalate. A method of obtaining a polyester having a specific catalytic metal amount and phosphorus amount by adding a titanium compound catalyst and a phosphorus compound, followed by a polycondensation reaction until a constant diethylene glycol content is reached under high temperature and reduced pressure is preferably employed. .
[0020]
The phosphorus compound added as a heat stabilizer is preferably phosphoric acid, phosphorous acid or the like.
[0021]
In the polyester of the present invention, in terms of heat resistance and molding processability, when M is the mmol% of the metal element of the catalytic metal component and P is the mmol% of the phosphorus element of the phosphorus compound, the M / P is 0.5. It is preferable that it is -5, and it is especially preferable that it is 0.5-3. However, when a plasticizer is added, M / P is preferably 0.01 to 2 in order to improve heat resistance.
[0022]
The polyester in the present invention preferably has a diethylene glycol component amount of 0.01 to 5 mol%, more preferably 0.01 to 3 mol%, to reduce changes in color tone and mechanical properties during high temperature molding. Desirable in terms.
[0023]
The intrinsic viscosity of the polyester in the present invention is preferably 0.5 to 1.5 (g / dl), and the intrinsic viscosity is particularly preferably 0.6 to 1.0 in applications where heat resistance and aging resistance are strictly required. (G / dl) is preferred.
[0024]
The biaxially stretched polyester film for molding according to the present invention has a longitudinal elongation at break (%) from 20 ° C. to (melting point−60) ° C. in terms of improving the moldability and impact resistance after the molding. It is necessary to satisfy the following formula (1) when the width direction breaking elongation (%) is measured and the values when the sum is maximum are respectively S1 and S2, and preferably (S1 + S2) / 2 is 310% or more and 1500% or less, more preferably 360% or more and 1300% or less, and particularly preferably 400% or more and 1000% or less.
[0025]
(S1 + S2) / 2 ≧ 300% (1)
As a method of setting the breaking elongation to the above value,
(1) A method in which a film preheated at a high temperature of 100 ° C. or higher in a longitudinal stretching step is stretched in a single step or a multi-step by 1.5 to 4.0 times,
(2) a method of reducing the stretching speed,
(3) How to relax the film during heat treatment,
(4) A method of adding a plasticizer to polyester,
Etc., and a film can be formed by combining these.
[0026]
Furthermore, when the film of the present invention is preheated before being processed and processed to be conveyed, the following formula (2) may be satisfied in terms of suppressing the thermal elongation of the film and improving the moldability. More preferably, (S2-50) is S1 or more, particularly preferably (S2-100) is S1 or more.
[0027]
S1 ≦ S2 ...... Formula (2)
In the polyester film of the present invention, the rate of change in haze after heating at 170 ° C. for 10 minutes is preferably 0 to 20%, particularly 0 to 15% from the viewpoint of heat resistance, particularly iron resistance. preferable. The haze can be achieved by using a polyester having a melting point of 210 to 280 ° C. and a crystal melting heat of 10 to 50 J / g, and controlling the orientation and crystal state during biaxial stretching.
[0028]
As a method,
(1) A method in which a film preheated at a high temperature of 100 ° C. or higher in a longitudinal stretching step is stretched in a single step or a multi-step by 1.5 to 4.0 times,
(2) a method of reducing the stretching speed,
(3) How to relax the film during heat treatment,
Is preferred.
[0029]
In the present invention, it is preferable to add a plasticizer to the polyester from the viewpoint of forming particularly severe processability and fine irregularities. Examples of the plasticizer added to the polyester include an ester plasticizer, an ether plasticizer, a phthalic acid plasticizer, and a phosphorus plasticizer. As addition amount, it is preferable to contain 1-50 weight% of plasticizers in polyester, and it is 2-30 weight% especially preferably.
[0030]
As the plasticizer used in the present invention, an ester plasticizer and an ether plasticizer are particularly preferable from the viewpoint of heat resistance and molding processability. As the ester plasticizer, those having a hydroxyl value of 0 to 20 (mg / g) are preferable from the viewpoint of heat resistance, and those having 0 to 15 (mg / g) are more preferable. The acid value is preferably 0 to 5 (mg / g), particularly preferably 0 to 3 (mg / g). Moreover, it is preferable that the melting | fusing point peak measured by DSC is 120-230 degreeC at the point of moldability, and it is especially preferable that it is 140-220 degreeC. The intrinsic viscosity is preferably 0.02 to 0.5 (g / dl) and particularly preferably 0.05 to 0.3 (g / dl) in terms of moldability and heat resistance. Among the ester plasticizers, polytrimethylene terephthalate, polybutylene terephthalate, or the like may be used, but a method of using a phosphorus compound or the like in combination is preferable in order to make transesterification difficult.
[0031]
As the ether plasticizer, a polyalkylene glycol plasticizer is preferable.
In the polyester plasticizer and the polyether plasticizer, it is preferable that end-capping is performed with a benzoic acid, an epoxy compound, a carbodiimide compound, or the like because the melting point of the polyester is not lowered or changed. As a ratio of terminal blocking, 50% or more, preferably 70% or more, particularly preferably 85% or more of all terminal groups are preferably blocked.
[0032]
In particular, from the viewpoint of improving processability and aesthetics, it is preferable to react a terminal blocker with a plasticizer, and it is preferable to react 0.01 to 100 mol of the endblocker with respect to 1 mol of the plasticizer. In particular, the melting point is preferably −150 ° C. or more and 100 ° C. or less, more preferably −100 ° C. or more and 60 ° C. or less, and particularly preferably the melting point, from the viewpoint of improving workability at low temperatures and mechanical properties. It is -50 degreeC or more and 20 degrees C or less. Further, the molecular weight of the plasticizer is preferably 100 to 2500 or less, more preferably 200 to 2400, particularly in terms of improving the mechanical properties at low temperatures.
[0033]
The biaxial polyester film for molding according to the present invention preferably contains particles in the film from the viewpoint of molding processability and handling. The particle diameter and the added amount are determined by the slipping property during molding and the lamination process. From the viewpoint of adhesiveness, it is preferable to add particles having a particle size of 0.01 to 10 μm, particularly those having a particle size of 0.01 to 5 μm. Moreover, it is preferable that the addition amount is 0.005 to 50 weight%, Most preferably, it is 0.01 to 30 weight%.
[0034]
Specifically, as inorganic particles, wet and dry silica, wet silica, colloidal silica, aluminum silicate, titanium oxide, calcium carbonate, calcium phosphate, barium sulfate, alumina, mica, kaolin, clay, etc. can be used to form a surface. From the viewpoint of properties, aluminum silicate and colloidal silica are preferable.
[0035]
As the organic particles, various organic polymer particles can be used. As the type thereof, particles having any composition may be used as long as at least a part thereof is insoluble in polyester. Moreover, various materials such as polyimide, polyamideimide, polymethyl methacrylate, formaldehyde resin, phenol resin, cross-linked polystyrene, silicone resin, a mixture thereof, and a copolymer resin can be used as the material for such particles. However, vinyl-based crosslinked polymer particles that have high heat resistance and can easily obtain particles having a uniform particle size distribution are particularly preferred.
[0036]
In the present invention, it is preferable to use a filter that cuts coarse particles of 30 μm or less and foreign matters, and particularly a filter that cuts 20 μm or less, in terms of improving aesthetics, when the polyester is melt-extruded. .
[0037]
The thickness unevenness of the film of the present invention is preferably 0 to 30%, more preferably 0 to 20%, from the viewpoint of improving uniformity in molding and haze characteristics. Here, the thickness unevenness is obtained by measuring the thickness at intervals of 20 cm in the longitudinal direction and the width direction of the film, and assigning the difference between the maximum value and the minimum value to the average thickness and displaying the percentage.
[0038]
In order to maintain the beauty after forming the film, it is preferable to satisfy the following formula (3). More preferably, H × d is 100 or more and 400 or less, and particularly preferably 100 or more and 300 or less.
[0039]
100 ≦ H × d ≦ 500 (Formula (3))
H: Haze (%)
d: Film thickness (μm)
Thus, in order to satisfy the formula (3), a method of reducing the film thickness within a range that does not deteriorate the molding processability, and to reduce haze, the stretching temperature is decreased within a range that does not deteriorate the molding processability, or the draw ratio. The method of increasing the catalyst, the method of making the catalyst composition of the polyester germanium compound, titanium compound, etc., the particles to be added are not particles with a large particle size distribution such as agglomerated silica, but particles close to monodisperse such as colloidal silica are preferred. It is preferable to have particles formed with an aggregation degree (= secondary particle diameter (μm) / primary particle diameter (μm)) of at least 10 or less as confirmed by observation with an electron microscope. More preferably, it is 5 or less. However, when it is composed only of primary particles, it is defined as an aggregation degree of 1.
[0040]
The film according to the present invention preferably has a thermal shrinkage of -5 to 5% when heat-treated at 170 ° C. for 30 minutes in order to improve the laminating property with the metal. More preferably, it is −4 to 4%, particularly preferably −3 to 3%.
[0041]
Furthermore, the biaxially stretched polyester film for molding according to the present invention is preferably a laminated film in order to particularly improve the molding processability, heat resistance, and beauty. Although it does not specifically limit as a laminated | multilayer film, When using the polyester A containing a plasticizer, it is preferable not to contain a plasticizer at least on one side or both surfaces, or to laminate | stack polyester B with a plasticizer content less than polyester A. .
[0042]
The thickness of the layer mainly comprising polyester B in the laminated film is not particularly limited, but when emphasizing moldability and aesthetics, it is preferably 0.001 to 10 μm, and more preferably 0.01 to 5 μm. Preferably there is. Although a laminated structure is not specifically limited, It is preferable to provide the layer used as A / B, B / A / B, B / A / C, and A / B / C with respect to polyester A containing a plasticizer.
[0043]
The thickness of the film of the present invention is preferably 8 to 1000 μm, more preferably 10 to 300 μm, and particularly preferably 30 to 200 μm in terms of moldability, heat resistance, and impact resistance.
[0044]
The method for producing the film in the present invention is not particularly limited. For example, after drying polyester as necessary, it is supplied to a melt extruder, extruded into a sheet form from a slit-shaped die, and casted by an electrostatic application method. There is a method for obtaining a film having a desired elongation at break by stretching and heat-treating the unstretched sheet in the longitudinal direction and the width direction of the film after the film is closely adhered and cooled and solidified.
[0045]
Among them, the tenter method is preferable from the viewpoint of the quality of the film, and after stretching in the longitudinal direction, a sequential biaxial stretching method in which the film is stretched in the width direction, and a simultaneous biaxial stretching method in which the longitudinal direction and the width direction are stretched almost simultaneously. Is desirable. As a draw ratio, it is preferable to draw 1.5 to 5.0 times in each direction, and more preferably 1.5 to 4.0 times. Either the stretching ratio in the longitudinal direction or the width direction may be increased or the stretching ratio may be the same. The stretching speed is desirably 1000% / minute to 1000000% / minute, and it is particularly preferable to form a film at a longitudinal stretching speed of 1500 to 300000% / minute, and more preferably 1800 to 100,000% / minute. . In particular, in the simultaneous biaxial stretching method, a stretching speed of 500 to 5000% / min is preferable. The stretching temperature may be in the range of 100 ° C. or higher and 150 ° C. or lower, and may be any temperature within this range, but (glass transition temperature + 20) ° C. to 60 ° C. is particularly preferable.
[0046]
Further, after this, the film is heat-treated, and this heat-treatment can be performed by any method such as in an oven or on a heated roll. The heat treatment temperature can be any temperature between 60 ° C. and 250 ° C., preferably 150 to 240 ° C. Moreover, although heat processing time can be made arbitrary, 0.1 to 60 second is preferable, More preferably, it is 1 to 20 second.
[0047]
The heat treatment may be performed while relaxing the film in the longitudinal direction and / or the width direction. Furthermore, re-stretching may be performed once or more in each direction, and then heat treatment may be performed.
[0048]
Moreover, it is preferable to further improve the adhesiveness by subjecting the film surface to a surface treatment such as a corona discharge treatment. The surface tension after the surface treatment is preferably 45 to 70 mN / m, and particularly preferably 50 to 65 mN / m.
[0049]
Various coatings may be applied to the film of the present invention, and the coating compound, method, and thickness thereof are not particularly limited as long as the effects of the present invention are not impaired.
[0050]
The polyester film for molding processing of the present invention is used for molding processing applications that are molded and processed in a laminated structure with a single substance or a nonmetallic material, and the purpose of use is not particularly limited, but the nonmetallic material is paper, nonwoven fabric, A glass or polymer material is preferable in terms of reducing the weight of the final product.
[0051]
Furthermore, in the laminated structure, an adhesive layer, a printed layer, or the like may be formed between the nonmetallic material. As the molding method, a single or plural molding processes such as laminate molding, vacuum molding, pressure molding, vacuum / pressure molding, in-mold molding, drawing molding, and bending molding may be performed, and the molding processing method is particularly limited. Not. In particular, as a molding method, in-mold molding, bending molding, or the like can be suitably used.
[0052]
When used alone, the molding process may be performed once or multiple times, such as vacuum molding, pressure molding, vacuum / pressure molding, in-mold molding, draw molding, bending molding, stretch molding, etc. Is not particularly limited.
[0053]
【Example】
Hereinafter, the present invention will be described in detail by way of examples. The characteristics were measured and evaluated by the following methods.
(1) Catalyst metal element amount, phosphorus element amount, M / P
The film was heated to (melting point + 20) ° C. and melted to prepare a circular disk, and the amount of catalytic metal element and the amount of phosphorus element were determined by fluorescent X-ray analysis. When determining the amount, a calibration curve with fluorescent X-rays obtained from a sample in which the amount of each metal element added was changed in advance was used.
[0054]
The metal component due to the particles in the film was obtained by removing the component. In addition, as a method of removing particles, for example, the film is dissolved in orthochlorophenol heated to 80 to 100 ° C., centrifuged, the particles are removed, and the polymer in the solution is precipitated, and then the fluorescent X-rays described above are used. There is a way to do the analysis.
[0055]
In the case of a laminated film, each layer was scraped off and obtained separately.
M / P was determined with M as the mmol% of the catalytic metal element and P as the mmol% of the phosphorus element amount.
(2) Content of diethylene glycol component in polyester
Measured by NMR (13C-NMR spectrum).
(3) Intrinsic viscosity of polyester
The polyester was dissolved in orthochlorophenol and measured at 25 ° C.
(4) Melting point of polyester
The polyester was melted and then rapidly cooled, and measured with a differential scanning calorimeter (DSC type 2 manufactured by Perkin Elmer) at a heating rate of 10 ° C./min, and the melting point was determined from the melting peak.
[0056]
In the case of a laminated film, each layer was scraped off and obtained separately.
(5) Film elongation at break (%)
Using a Tensilon (tensile tester), measurement was performed in increments of 10 ° C. from 20 ° C. to (melting point−60) ° C. The measurement is performed by keeping the film at the measurement temperature for 3 minutes, measuring the breaking elongation (%) in the film longitudinal direction and the width direction at 10 points, respectively, with a pulling speed of 300 mm / min, a width of 10 mm, and a sample length of 50 mm. It was. From the values of the respective temperatures, the values of the breaking elongation when the sum of the breaking elongations in the longitudinal direction and the width direction takes the maximum values were defined as S1 and S2, respectively.
(6) Average particle diameter and degree of aggregation
The resin is removed from the film by plasma low-temperature ashing to expose the particles. The processing conditions are selected such that the resin is incinerated but the particles are not damaged. This was observed with a scanning electron microscope for 5,000 to 10,000 particles, and a particle image was obtained from the equivalent circle diameter by an image processing apparatus. When the particles are internal particles, the film cross section is cut to create an ultrathin section having a thickness of about 0.1 to 1 μm, and a photograph is taken at a magnification of about 5000 to 20000 (10 sheets: 25 cm × 25 cm) using a transmission electron microscope. ) The average dispersion diameter of the internal particles was calculated from the equivalent circle diameter. The degree of aggregation (= secondary particle diameter (μm) / primary particle diameter (μm)) confirmed by observation with an electron microscope was also determined.
(7) Thermal contraction rate
The film sample was measured for thermal shrinkage according to JIS C2318. However, the holding time of the oven was 30 minutes, and the temperature was 170 ° C.
(8) H × d, change rate of haze
The haze (%) determined by SEP-H-2 turbidimeter (Nippon Seimitsu Optical Co., Ltd.) in accordance with JIS-K-6714-58 was set as H. Thickness d (μm) was obtained by measuring 100 points in total, 10 points in the vertical direction and 10 points in the horizontal direction at an interval of 5 cm using an electronic micrometer.
[0057]
The change rate of haze is obtained by calculating the haze of a film treated in a hot air oven at 170 ° C. for 10 minutes and the film before treatment, and the change rate (%) of haze is (haze after treatment−haze before treatment) ÷ It calculated | required from the haze x100 before a process.
(9) Thick spots
The thickness in the longitudinal direction and the width direction was measured with a digital thickness meter at intervals of 20 cm to obtain thickness spots. Here, the thickness unevenness is obtained by measuring the thickness at intervals of 20 cm in the longitudinal direction and the width direction of the film, and assigning the difference between the maximum value and the minimum value to the average thickness and displaying the percentage.
(10) Embossing processability
After bonding a biaxially stretched polyester film for molding and a commercially available PET biaxially stretched film (Toray Industries, Inc. “Lumirror” S type 50 μm) with a urethane adhesive, roll heating (140 ° C.) The biaxially stretched polyester film side for molding is heated by heating immediately prior to concentrating radiation, and after passing through an embossing roll (30 μm high unevenness, 3 μm high unevenness), a cooling roll (40 ° C.) It was cooled with. The embossability of the obtained film was determined as follows. The beauty was determined by the absence of color change, wrinkles, and no glare.
A: The uneven shape of the embossing roll is excellently formed on the film side, both large and small. Good beauty.
○: A large portion of the embossing roll having a large uneven shape is formed on the film side. There is almost no change in beauty.
(Triangle | delta): Although the uneven | corrugated shape of an embossing roll is formed in the film side, an unevenness | corrugation is slightly shallow.
A change in beauty is also observed.
X: The embossing roll has an uneven shape on the film side, but the unevenness is shallow, and the change in beauty is large.
(11) Heat resistance
The film formed and processed in the above (10) was brought into contact with a commercially available steam iron, and the heat resistance was evaluated based on the degree of visual surface change.
A: No change in color and shape
○: Almost no change in color and shape
Δ: Some change in either color or shape.
X: Change is seen in both color and shape.
(12) Vacuum / pneumatic formability
A biaxially stretched polyester film for molding and a PET nonwoven fabric were bonded together with a urethane-based adhesive, and then vacuum-pressure forming was performed at 150 ° C., and the determination was made as follows.
○: Good moldability without uneven thickness and whitening.
Δ: Almost no uneven thickness and whitening, and good moldability.
X: Uneven thickness: There is whitening, and formability is poor.
Examples 1-6, Comparative Examples 1-3
In Example 1, polyester was polymerized using calcium compound catalyst, antimony compound catalyst, phosphoric acid (M / P = 2.0) and colloidal silica particles (average diameter 0.8 μm, cohesion 1) as particles. The obtained polyester chip is sufficiently vacuum dried at 160 ° C., confirmed that the moisture content is 10 ppm, melt-extruded at 280 ° C. using a nitrogen purged hopper, and electrostatically applied with a wire electrode. However, it was rapidly cooled and solidified on the cast to obtain an unstretched film.
[0058]
This unstretched film was simultaneously biaxially stretched at a temperature of 105 ° C. (longitudinal and transverse stretching ratio: 2.8 times, longitudinal stretching speed: 2000% / min) with a linear motor type simultaneous biaxial stretching machine, and 200 Heat treatment was carried out at 5 ° C. for 3 seconds at 5 ° C. to obtain an 80 μm film. The obtained film characteristics are shown in Table 1. Molding processability, impact resistance, and heat resistance were all good.
[0059]
In Example 2, isophthalic acid copolymerized PET was polymerized using titanium / silica catalyst (molar ratio 9/1), phosphoric acid and wet silica particles (average diameter 1.2 μm, aggregation degree 150) as particles (here M / P = 0.9). The obtained polyester chip was sufficiently vacuum-dried at 160 ° C., and after confirming that the moisture content was 20 ppm, it was melt-extruded at 280 ° C. using a nitrogen purged hopper and applied to the surface of the casting drum at 60 m / min. While forming a water film and applying static electricity with a tape-like electrode, it was rapidly cooled and solidified on a cast to obtain an unstretched film. The obtained unstretched film was formed by a tenter sequential biaxial stretching machine. The conditions at that time are a longitudinal stretching temperature of 108 ° C., a longitudinal stretching ratio of 3.2 times (stretching speed of 120,000%), a transverse stretching temperature of 115 ° C., a transverse stretching ratio of 2.9 times, a heat treatment temperature of 210 ° C., and a relaxation of 5%. . A film having a thickness of 60 μm was obtained under the above film forming conditions. The obtained film characteristics are shown in Table 1. Molding processability, impact resistance, and heat resistance were all good.
[0060]
In Example 3, polyester obtained by adding 5% of an ester plasticizer polysizer A-51 (melting point: 195 ° C.) manufactured by Dainippon Ink & Chemicals, Inc. as a plasticizer to the polyester of Example 1 was used as the B layer. A laminated film B / A / B having a polyester layer A (lamination ratio 1: 8: 1) was formed in the same manner as in Example 1 to obtain a 45 μm film. The obtained film characteristics are shown in Table 1. In particular, the embossing processability of 3 μm was excellent.
[0061]
In Example 4, polyester B in which the melting point of the plasticizer was changed to 150 ° C. was used, and a film was formed with a sequential biaxial stretching machine with a laminated structure of A / B / A (longitudinal stretching speed of 110000% / min. The film forming conditions are the same as in Example 2 except for the above. The film thickness was 50 μm. The obtained film characteristics are shown in Table 2. In particular, the unevenness forming property of 30 μm by embossing was good.
[0062]
In Example 5, the polyester and particles (cohesion degree 700) were changed, and the film forming conditions of Example 2 were reduced to a longitudinal stretching temperature of 100 ° C., a longitudinal stretching ratio of 2.5 times, and a stretching speed of 500,000% / When the final film thickness was 45 μm, the thickness unevenness was 23%, and the moldability was slightly lowered.
[0063]
In Example 6, a copolymerized polyester was formed under the same film forming conditions as in Example 5 to obtain a 40 μm film. However, since the melting point was low, the results were slightly inferior in heat resistance and beauty.
[0064]
As Example 7, the catalyst composition of Example 1 was Ge 20 mmol% and phosphorus 20 mmol%, the longitudinal and transverse stretching temperatures were reduced by 3 ° C., respectively, and the film thickness was 50 μm (haze 3%). In-mold molding was performed by injecting polycarbonate having a height of 3 mm and a height and width of 1 cm on the surface. When the evaluation judgment was performed from the non-deposited surface in the same manner as the vacuum / pressure forming, it was at the level “◯”. The degree of aggregation of the particles was 1.
[0065]
As Example 8, 5% by weight of KRM-4004 (end-capped polyether plasticizer) manufactured by Sanyo Chemical Industries, Ltd. was added as a plasticizer to the polyester of Example 1, the longitudinal stretching temperature was 95 ° C., and the transverse stretching temperature was A 60 μm film was obtained in the same manner as in Example 1 except that the temperature was 100 ° C. Vapor deposition was performed on the obtained film, and in-mold molding was performed by injecting polycarbonate having a height of 3 mm and a height and width of 1 cm on the deposition surface. Evaluation and judgment were performed from the non-deposited surface in the same manner as in vacuum / pressure forming, and it was found to be at the ◯ level and excellent in-mold formability. Further, the obtained film was particularly excellent in embossability (Table 4).
[0066]
As Example 9, 20% by weight of polypropylene terephthalate (IV = 1.1, Ti 15 mmol%) and a phosphorus compound (Adeka Stub AX-71 manufactured by Asahi Denka Kogyo Co., Ltd.) as a plasticizer were added to the polyester of Example 1 as a whole. A film having a thickness of 40 μm was obtained in the same manner as in Example 1 except that / P was added to 0.2, the longitudinal stretching temperature was 85 ° C., and the lateral stretching temperature was 105 ° C. Vapor deposition was performed on the obtained film, and in-mold molding was performed by injecting polycarbonate having a height of 3 mm and a height and width of 1 cm on the deposition surface. When the evaluation judgment was performed from the non-deposited surface in the same manner as the vacuum / pressure forming, it was at the level “◯” and was excellent in in-mold formability (Table 4).
[0067]
Comparative Examples 1-3
A 50 μm film was formed using each of the polyesters shown in Table 3. The obtained film characteristics are shown in Table 3, all of which were inferior in moldability and heat resistance (in addition, the aluminum silicate of Comparative Example 1 has a cohesion of 1).
[0068]
Comparative Example 4
As Comparative Example 4, the particles of Comparative Example 1 were agglomerated silica, the average particle diameter was 1.5 μm, the amount of added particles was 0.2%, the film thickness was 100 μm (haze 6%), and vapor deposition was performed. In-mold molding was performed by injecting 3 mm of polycarbonate having a length and width of 1 cm. When the evaluation judgment was performed from the non-deposition surface in the same manner as the vacuum / pressure forming, it was at the x level. The degree of aggregation of the particles was about 500.
[0069]
Those using the polyester film of the present invention were excellent in moldability, beauty and heat resistance.
[0070]
[Table 1]

[0071]
[Table 2]

[0072]
[Table 3]

[0073]
[Table 4]

[0074]
In addition, the symbol in a table | surface is as follows (a numerical value is the mol% in an acid and a glycol component).
[0075]
TPA: terephthalic acid
IPA: Isophthalic acid
EG: Ethylene glycol
DEG: Diethylene glycol
CHDM: cyclohexanedimethanol
NDC: Naphthalenedicarboxylic acid
M: concentration of catalytic metal element remaining in the film (mmol%)
P: Indicates the concentration (mmol%) of phosphorus element remaining in the film. )
Ti / Si: Titanium, silica composite oxide
Ge: Germanium compound
Sb: antimony compound
Ca: Calcium compound
[0076]
【The invention's effect】
The biaxially stretched polyester film for molding process of the present invention is excellent in molding processability, impact resistance, heat resistance and beauty when laminated with a single substance or a nonmetallic material, and is suitable for many molding process materials. Can be used.

Claims (10)

Polyester having a melting point of 210 to 280 ° C. as a main constituent, satisfies the following formula (1), and is formed by vacuum / pressure forming or embossing in a single layer or a laminated structure with a nonmetallic material. A biaxially stretched polyester film for molding which is an axially stretched polyester film and has a haze change rate of 0 to 20% after heating at 170 ° C. for 10 minutes.
500 ≧ (S1 + S2) / 2 ≧ 360 % ...... Formula (1)
S1, S2: Longitudinal breaking elongation (%) and width breaking elongation (%) are measured within the range of 20 ° C. to (melting point−60) ° C., and the values when the sum becomes maximum are respectively S1 , S2. 2. The biaxially stretched polyester film for molding according to claim 1, wherein the polyester constituting the main constituent is one having a melting point of 246 to 280 ° C. 3. Each value of S1 and S2 satisfies following formula (2), The biaxially stretched polyester film for shaping | molding of Claim 1 or 2 characterized by the above-mentioned.
S1 ≦ S2 ...... Formula (2) The haze H value (%) and the film thickness d (μm) satisfy the relationship of the following formula (3), and the biaxial stretching for forming according to any one of claims 1 to 3 Polyester film.
100 ≦ H × d ≦ 500 (Formula (3))
H: Haze (%)
d: Film thickness (μm) The biaxially stretched polyester film for molding according to any one of claims 1 to 4, comprising 1 to 50% by weight of a plasticizer. The biaxially stretched polyester film for molding according to any one of claims 1 to 5, wherein the polyester film has a laminated structure. The biaxially stretched polyester film for molding process according to any one of claims 1 to 6, wherein the biaxially stretched polyester film is subjected to a molding process after being laminated with a nonmetallic material. The biaxially stretched polyester film for molding according to any one of claims 1 to 7, wherein the non-metallic material is a kind selected from paper, non-woven fabric, glass and polymer material. A molded laminated body obtained by molding the biaxially stretched polyester film for molding according to any one of claims 1 to 8 in a laminated configuration with a nonmetallic material. A molded laminate obtained by molding the biaxially stretched polyester film for molding according to any one of claims 1 to 8 with a material and a laminated structure selected from paper, nonwoven fabric, glass, and a polymer material.